As you likely could have guessed, the Hollywood stars are pumped for their longtime co-worker.

"He's going to be amazing," Jodie shared with E! News. "We joke that he's the baby whisperer on set because he's amazing with kids."

And while the cast doesn't know the sex of John's baby, there's no doubt from close friends that the excitement is real.

"I think he's wanted to do it for a long time. I think it was just a matter of finding the right person and timing and all of that kind of stuff," Jodie added. "I texted him and said 'I can't wait to spoil the new baby.' We love Caitlin. She's great."

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Another thing that's more than great is the fact that the entire cast managed to stay close since they last worked together.

For Barber, seeing the set again was a bit surreal, but all in all, it felt very natural to return, since she and Sweetin grew up on the show.

"It was very natural for us because we grew up on set and when we first saw the set for the first time coming back, it was a little surreal but now it's just hanging out," she explained to Justin Sylvester and Morgan Stewart .

Fuller House returns with new episodes on Netflix starting Friday, December 22.